Burner for solid fuels



May 1s, 1937.

v. M. RAu|KsHANK BURNER FOR SOLID FUELS s shetssneet 1 Filed Sept. 1,1933 INVENTOR V'nzlus M. CraSam/o ATTORNEYS May 18, 1937 v. Mc-:UIKSHANK2,080,410

BURNER FOR SOLID FL-JELS Filed Sept. 1, 1953 3 Sheets-Shea?I 2 ATTORNEYSMay 18, 1937. v. M cRulKsHANKr A 2,080,410

BURNER FOR SOLID FUELS ATTORNEYS Patented May 18, 1937 UNITED STATESFATENT OFFICE 11 Claims.

This invention relates to burners for coal or other similar solid fuels,in which the burner includes fuel, fire and ash supporting means overwhich the unignited or green fuel and re bed is moved or impelled in acomparatively shallow layer either radially inward or radially outwardfrom a point or points of fuel supply to a point or region where theashes and residue are discharged, it being understood that the movementof the fuel and re bed over the supporting means is at such a rate ofspeed, proportionate to the air supply or rate of combustion that thesame is completely consumed by the time it reaches the region ofdischarge of the ashes and residue, while providing sufficient agitationof the fire bed to prevent clinker formation. The burner furtherincludes guide means with which the fuel, fire bed and ash supportingmeans cooperate to effect the movement of the fuel and fire bed from thepoint or points of supply to the region of discharge of the ashes andresidue.

The invention ccmprehends a guide means of the indicated character, thesurface or surfaces of which are water-backed so as to prevent the 25fusing of ashes or cinders thereto thus avoiding collections thereonwhich would tend to alter their shape and interfere with theeffectiveness or operativeness of the impelling means.

More particularly the invention resides in a water-backed guide meanswhich may be fashioned as either an integral part of the fuel supplyconduit or as a separate element and through which conduit the fuel istransmitted to the point or points of supply of the fuel to a grateelement, the arrangement being such as to provide a barrier against theignition of the fuel in the supply conduit by the nre on the grateelement due to the continuous relative change or shifting of the portionof the grate and the fire bed with reference to the fuel supply outlet.

As a further feature, the invention aims to provide a burner in whichthe fuel, re and ash supporting means are driven and rotated withreference to fixed water-backed guide means so as to cause the movementof the fuel, fire bed and ashes radially over said supporting means andin which, if desired, certain of said means are driven at relativelydiiferent rates of speed.

The invention further embodies, in a burner of the character set forth,fuel, fire bed and ash supporting means which are so constructed andarranged as to automatically effect the discharge 55 of dirt and ashestherefrom in order to avoid any appreciable collection on the surfacesthereof which might interfere with the proper operation of the burner.

The invention further contemplates a supporting member which is sofashioned as to provide means for causing a horizontal draft from adraft chamber to be directed away from the point or points of fuelsupply and the guide means so as to drive the ame radially away from thesupply, thereby further insuring against ignition of fuel in supplywhile aiding in the preventing of fusing of the material on the surfaceor surfaces of the guide means.

With particular reference to a guide means. which forms a part of anoutlet conduit through which the fuel is fed onto a rotating fuel andfire bed support, the invention comprehends the provision of a fulcrumedand weighted mounting for said support to insure proper contact of thesame with the combined fuel conducting and guide means, thus making forfree relative movement of the parts and obviating binding.

The invention further provides ash and cinder cutting means to preventclogging and to insure of the proper discharge of the ashes and cinders.

Other objects of the invention are to provide a more practical burner ofthe indicated character, which embodies comparatively few and simpleparts, capable of economical production, assemblage and installation andwhich burner is highly eflicient for the purpose intended.

With the above and other objects in view, reference is had to thefollowing specification and accompanying drawings in which there aredisclosed various forms of the invention while the claims covermodifications which properly fall within their scope.

In the drawings:

Fig. 1 is a fragmentary, vertical sectional view through a furnaceequipped with a burner constructed in accordance With one form of theinvention.

Fig. 2 is a horizontal, sectional View therethrough, taken aproximatelyon a plane indicated by the line 2-2 in Fig. v-1.

Fig. 3 is a sectional plan view taken on a plane indicated by the line3--3 in Fig. 1.

Fig. 4 is a perspective view of the upper rotary clean-out plate asviewed from the underside.

Fig. 5 is a fragmentary side elevation illustrating a modified form offuel feed and guide means.

Fig. 6 is a bottom plan view thereof.

Fig. 7 is a vertical sectional View of a further modification.

Fig. 8 is a vertical sectional view of a still further modication.

Fig. 9 is a fragmentary sectional plan view taken approximately on theline 8--9 of Fig. 8.

Fig. l is a vertical sectional View of a modified form of the fuelconduit and guide means.

Referring to the form of the invention illustrated in Figs. 1 to 4inclusive, A designates the furnace wall and B a funnel shaped fuel feedhopper which constitutes a part of the boiler section, the same. beingformed to provide a waterjacket C so that the hopper is properlywaterbacked.

In this form of the invention, the burner includes a combined fuel, firebed and ash supporting member, designated generally by the referencecharacter D, and a combined fuel conduit and guide means E, the latterbeing shown in this instance, as an integral part of the fuel feedhopper B into which the water jacket C extends. The member E is open atits upper and lower ends and is provided with a side fuel outlet IGwhich is in the nature of a notch or recess opening through the lowerend of said member with the Vertical side walls II and I2 of the fueloutlet diverging outwardly, the wall I2 being convex to serve as a guidesurface. It will also be observed that the member E is provided with anextension I3 providing a sharp vertical edge which protrudes inwardlybeyond the inner periphery M, the leading surface of which extensionmerges into the wall i2 .so as to cut the fuel column within the memberE and initially urge the same outwardly through the side outlet I0 asthe fuel column resting upon the fuel support is rotated therewith.

In order to promote circulation of the water in the water-jacketed orwater-backed portion of the member E, a circulation pipe I5 extendsdownwardly within the member E and extends through and communicates withthe waterjacketed or water-backed portion. A single circulating pipe I5is employed where the member E forms an integral part of the member Bbut in event the member E is made asa separate section from the memberB, as shown in Fig. l0 two circulating pipes iS and vI'I will beemployed to obtain the proper circulation.

The fire bed supporting portion of the member D is made up of aplurality of grate plates or sections 26 having draft openings orperforations 2l. These plates or sections have upwardly and outwardlyflared inner edges 22 and curved rabbeted under surfaces 23 at theirouter edges. The fuel supporting portion of the member D includes acentral portion or hub 24 having secured thereto radially projectingspider arms 25 and an outer rim 26 which support the grate plates orsections 2B. The inner marginal portion of the plates between the.spider arms are supported on radial lugs 27, cast or otherwise formed onthe outer periphery of the central portion or hub 24. The upper portionof the hub 24 is provided with an extension 28 which is formed with anupwardly and outwardly curved and flared surface 29 slightly spaced fromthe inner outwardly and upwardly curved edges 22 of the plates to definedraft passages 36 between the lugs 2'! and spider arms 25, as shown inFig. 2, the purpose of which will be hereinafter set forth. The sidemargins of the plates rest upon adjacent spider arms 25 and the platesare removably secured in position b y screws 3| which pass therethroughand are threadedly anchored in the rim 26. The lower face of the rim 26is machined or faced and rests upon and is adapted for turning movementover the upper machined or faced upper edge 32 of the cup shaped body 33which, together with the fire bed or grate and its support, defines adraft chamber 34. The body 33 has a radially outwardly projecting airintake pipe 35 which communicates therewith and extends outwardlytherefrom and connects and communicates with the outlet 36 of a blower31. The motor 38, preferably an electric motor, drives the blower 31 anda shaft 39 which extends through the intake pipe 35 and into the draftchamber 34, the inner end of said shaft being journaled in a bearing itlwhich is supported on a bracket arm 4I located within the draftchamber. The spider arms have secured thereto a concentric ring orannulus 42 having depressions 43 opening through the under side thereofto receive the teeth lli of a drive pinion i5 which is secured to theshaft 39 whereby rotation is imparted to the. member D, the same beingturned in the direction indicated by the arrow in Fig. 2 of thedrawings.

The coal or fuel feeds by gravity from the hopper member B into thecombined conductor and impeller means E and obviously, the turningmovement of the member D in the direction indicated by the arrow causesthrough the gravitational feed of the fuel against the impeller face I2,a radial outward movement of the fuel in a shallow layer, the blowerfunctioning to supply air to the draft chamber 34 from whence the airdraft emerges upwardly through the openings or perforations 2| andthrough the burning fuel bed. At the same time, it will be observed thatthe passage 3D defined between and by the surfaces 22 and 29, effects anoutwardly directed horizontal draft which drives the flame radially awayfrom the supply, thereby further insuring against ignition of the fuelat the point of supply, while aiding and preventing the fusing ofmat-arial onto the guide surface or surfaces.

If desired, a pusher lug i8 may be formed on the upper surface of thehub within the member E and protruding upwardly therefrom to impartrotation to the fuel within the member E so as to more positively insurethe feeding and impelling of the fuel. It will also be observed that theupper surface of the portion 2li engages with and turns with referenceto the lower surface of the member E thus avoiding the escape of fuelbetween said surface and from the member E except through the sideoutlet opening iii.

The upper surface 0f the central portion 2d is formed with a funnelshaped depression or recess 46 from which a tubular shaft if leadsdownwardly through the portion 2li and through the bottom of the body33. The under side of the portion 2li is formed with a cylindricaldepression 48 which accommodates a tubular upstanding boss 49 protrudingupwardly from the bottom of the draft chamber 34 and through whichtubular boss the tubular shaft 4l extends. The funnel shaped depressionl5 pockets the fuel and any excess water in the fuel supply will bedrained and conveyed away through the tubular shaft lil' which acts as adrain pipe for said excess water or moisture so that it is dischargedbelow the fire bed and into a suitable receptacle in an ash space in thelower part of the furnace.

A clean-out means is provided for removing from the draft chamber ashdust, coal dust, cr other particles which find their way into thechamber through the openings or apertures 2I. As illustrated, theclean-out means consists of a discharge opening 50 in the bottom wall ofthe draft chamber body 33 and upper and lower rotary plates 5| and 52provided with diametrically oppositely disposed outlet openings 53 and54. The lower plate 52 is suitably keyed to the lower end of the tubularshaft 41 and is driven by and with said shaft while the upper plate isdriven by means of a depending stud 55 on one of the spider arms 25which engages with aradial arm 56 on the upper clean-o-ut plate 5|. Theupper plate 5| is fashioned to provide an upwardly 01T- set spiralledarm 51, the lower surface of which is slightly above the lower surfaceof the plate 5|, which arm has its free end disposed in the direction ofrotation of the plate to serve as a means for gathering up and impellinginwardly the solid matter which collects in the bottom of the draftchamber 34. The lower surface of the plate 5|, at the juncture of thearm 51 therewith, is extended for a distance and underlies the arm andis so fashioned as to provide a plow or shoe portion 58 having a pointedleading end facing in the direction of turning movement of the plate.The plow of shoe portion 58 functions to cleave through and part theparticles of matter collected on the bottom of the draft chamber so thatthey are either directed within the opening 53 or diverted outwardly tobe subsequently engaged and directed inwardly by the arm as it movesaround. This construction and arrangement avoids any tendency of theparticles to work under and lift the plate 5| so as to interfere withits proper operation. The upper plate 5| is formed with a centralopening 59 which accommodates the upstanding tubular boss 49 which bossserves as an axle about which the plate 5| turns.

In some instances, the member D may include a separate annular sectionor ash ring 5|] which, if desired, may be driven at a relativelydifferent rate of speed. As shown, the ash ring B0 is supported with itsupper surface in a plane slightly below the plane of the upper surfaceof the grate plates 2|] and with the inner marginal portion disposedunder the concave rabbeted edges 23 of said grate plates or segments 20.A supporting annulus 6| is provided which is mounted to turn about theupper edge of the draft chamber body 33 and rests upon the upper surfaceof an annular bead 62 which is provided with downwardly flared apertures63. The rim 26, in this instance, is provided with an outwardly beveledouter surface overlying the upturned flange 65 at the inner marginaledge of the annulus 6|. This construction serves to deflect andpractically ,eliminate the entrance of ash dust between the confrontingsurfaces of the inner edge of the annulus 6| and. the outer surface ofthe draft chamber body 33 so as to prevent such material from reachingthe upper bearing surface of the bead 62. However, the openings 63 willrid the upper surface of the bead 62 o-f any dust which reaches thesame, so as to make for a smooth and unhampered turning movement of theash annulus and ash ring. The annulus 6| is provided with a series ofupstanding studs 66 upon which the ash ring rests, each stud beingprovided with a reduced upwardly projecting end 61 which extends througha corresponding opening 68 in the ash ring whereby the ash ring will beturned with the annulus. The annulus is provided in its under surfacewith an annular concentric series of depressions 69 to receive the teeth10 of a pinion 1| keyed to the drive shaft 39. Obviously, the pinions 45and 1| may be of such a ratio as to drive the grate and ash ring atrelatively different speeds.

If desired, ash cutters and impellers may be employed in connection withthe ash ring and as shown, such cutters and impellers consist ofnon-circular shanks 15, the lower ends 15 of which are received incorrespondingly shaped sockets 11 in the studs 66. The upper portions ofthe shanks are formed with blades 18 having converging inner and outerfaces 19 and 80, the blades being directed inwardly at an angle toeffect the cutting or breaking up of the ashes or cinders on the ashring and the outer faces functioning as impellers for pushing or cammingthe ashes and cinders radially outward over the outer marginal edge ofthe ash ring.

The hopper member B may be made of the closed sealed type, except forthe outlet l0, and means may be provided for supplying air thereto underpressure from the blower outlet 36 such as a conduit 8|. This functionsto circulate pure air in the hopper and also to circulate the samethrough the outlet Il! to insure against explosive and obnoxious gasesforming in the fuel hopper and for driving the same off to be consumedin the combustion chamber.

In order to provide means to further insure against clogging by oindersor clinkers and to break up and force the same downwardly between theouter edge of the ash ring and the inner surface of the furnace wall A,one or more breaker shoes B2 are provided which are in the nature ofangle bars attached to the inner surface of the furnace wall andinclined downwardly in the direction of turning movement of the ash ringor grate.

In order to hold the upper surface of the central portion 24 of themember D in intimate contact with the lower end of the member E, the rebed or grate element and the draft chamber, as Well as the blower andmotor, are preferably fulcrumed on the furnace Wall A, as shown by meansof trunnions 85 projecting laterally from a casting 86 on the pipe 35.The trunnions are mounted in bearings 81 provided on a plate 88 which isattached to the furnace wall. The outer end of the unit is providedwitha weight holder 89 upon which weights 55 are arranged to slightlyoverbalance the outer end of the unit so as to impinge the upper surfaceof the hub 24 against the lower end of the member E.

In the form of the invention illustrated in Fig. 5, the member G isformed as an integral part of the member I-I which defines a combinedpart of the boiler section and the fuel discharge chute. In thisinstance, however, the outer surface of the vertical Wall III] of themember G is helical or volute and the fuel outlet is located slightlyabove the member G at the root of the helical or volute surface so thatan underlying fuel support and grate member conveys the fuel supplyaround the helical or volute surface of the wall |||J from the point ofsupply of the fuel at the root and closer to the axis of the member G tothe point of said surface farthest from the axis, thus effecting agradual radial outward movement of the fuel thereover.

In the form of the invention illustrated in Fig. '7, the stationary fuelguide member 5 is hollow and disposed under the fuel outlet I6 and abovethe solid or central portion of the rotating fuel and fire bedsupporting means ||1. A conduit ||8 is connected to and communicateswith the interior of the member l5 and affords means for circulation ofwater to the member to prevent fusing of ashes or oinders onto thesurface thereof. This circulation may either be from the boiler sectionH9 or from any other suitable source of supply.

In the modified form of the invention illustrated in Fig. 8 of thedrawings, i20 represents the boiler section which also defines a fuelhopper l2| having a plurality of circumferentially arranged fuel outlets|22. In this instance, the fuel and iire bed support E23 underlies theboiler section and is rotated with reference thereto and the fueloutlets are disposed adjacent the outer marginal edge of the iire bed orgrate element, while the walls of the boiler section carry below eachfuel outlet a fixed fuel guide |24 which is so constructed and arrangedas to effect the radial inward movement of the fuel over the fuel andfire bed support 23. The fuel and fire bed support, in this instance,has a central outlet opening |25 through which the ashes, cinders andother residue gravitate into a subterposed receptacle therefor.

What is claimed is:

1. In a device for burning solid fuels, a fixed fuel conduit havingcommunication at its upper rend with an overhead fuel reservoir andhaving an open lower end provided with a notch defining a side outletthrough which the fuel is adapted to be discharged, a driven rotatablemember having a central fuel supporting portion underlying the conduit,and a fire bed supporting portion surrounding said fuel supportingportion, means pivotally mounting said member on a horizontal axis andmeans for over-balancing the member to hold the same in contact with thelower end of the conduit.

2. In a burner for solid fuels, a fixed vertically disposed tubular fuelconduit having an open lower end provided with a notch defining a sideoutlet through which the fuel is adapted to be discharged, a drivenrotatable fuel and re bed support having a fuel supporting portionthereof located under said conduit and the fire bed supporting portionsurrounding the fuel supporting portion, a wall of said outlet beingspirally curved and extended inwardly to provide a guide surface againstwhich the fuel, rotated by the fuel support, is impinged and movedradially outward through the fuel outlet and over the re bed supportingportion, said support having adjacent the juncture of the fuel and firebed supporting portions, circumferentially arranged upwardly andoutwardly directed air passages.

3. In a burner for solid fuels, a fixed vertically disposed tubular fuelconduit having an open lower end provided with a notch defining a sideoutlet through which the fuel is adapted to be discharged, a drivenrotatable fuel and re bed support having a fuel supporting portionthereof located under said conduit and the fire bed supporting portionsurrounding the fuel supporting 'portion a wall of said outlet beingspirally curved and extended inwardly to provide a guide surface againstwhich the fuel, rotated by the fuel support, is impinged and movedradially outward through the fuel outlet and over the lire bedsupporting portion, an annular ash and residue receiver and supportextending around the outer margin of the fire bed support and means fordriving the same.

4. In a burner for solid fuels, a fixed vertically disposed tubular fuelconduit having an open lower end provided with a notch defining a sideoutlet through which the fuel is adapted to be discharged, a drivenrotatable fuel and fire bed support having a fuel supporting portionthereof located under said conduit and the fire bed supporting portionsurrounding the fuel supporting portion, a wall of said outlet beingspirally curved and extended inwardly to provide a guide surface againstwhich the fuel, rotated by the fuel support, is impinged and movedradially outward through the fuel outlet and over the re bed supportingportion, and an annular ash and residue receiver and support extendingaround and disposed slightly below the outer margin of the fire bedsupport and a common means for driving said fuel and ash supports atrelatively different rates of speed.

5. In a burner for solid fuels, a fixed vertically disposed tubular fuelconduit having an open lower end provided with a notch defining a sideoutlet through which the fuel is adapted to be discharged, a drivenrotatable fuel and fire bed support having a fuel supporting portionthereof located under said conduit and the fire bed supporting portionsurrounding the fuel supporting portion, a Wall of said outlet beingspirally curved and extended inwardly to provide a guide surface againstwhich the fuel, rotated by the fuel support, is impinged and movedradially outward through the fuel outlet and over the fire bedsupporting portion, and an annular ash and residue receiver and supportextending around and disposed slightly below the outer margin of thefire bed support, means for driving said fuel and ash supports, andmeans carried by said ash and residue support for cutting the ashes andresidue and for impelling the same radially over the outer marginthereof.

6. In a burner for solid fuels, a fixed vertically disposed tubular fuelconduit, having an open lower end provided with a notch defining a sideoutlet through which the fuel is adapted to be discharged, a drivenrotatable fuel and fire bed support having the fuel supporting portionthereof located under said conduit and in wiping contact therewith andthe re bed supporting portion thereof surrounding said fuel supportingportion and extending outwardly beyond the conduit, a Wall of saidoutlet being spirally curved inwardly to provide a guide surface againstwhich the fuel rotated by the fuel support is impinged and caused tomove radially outward thereover and pusher means upstanding from saidsupport and within the conduit for imparting rotary motion to the fuel.

7. In a burner for solid fuels, a fixed vertically disposed tubular fuelconduit, having an open lower end provided with a notch defining a sideoutlet through which the fuel is adapted to be discharged, a drivenrotatable fuel and fire bed support having the fuel supporting portionthereof located under said conduit and in wiping contact therewith andthe fire bed supporting portion thereof surrounding said fuel supportingportion and extending outwardly beyond the conduit, a wall of saidoutlet being spirally curved inwardly to provide a guide surface againstwhich the fuel rotated by the fuel support is impinged and caused tomove radially outward thereover, said fuel and fire bed support having afunnel shaped depression in the region under said conduit and an outletleading downwardly therefrom to drain off moisture from the fuel.

8. In a device for burning solid fuels, a stationary upright tubularfuel conductor having an open lower end provided with a notch defining aside outlet through which the fuel is adapted to be discharged, a rotaryfuel support underlying and closing the lower end of the conductor andextending outwardly therebeyond, and means for rotating said support,said fuel outlet having a curved guide wall towards and against whichthe fuel rotated by the fuel support is impinged and by which wall saidfuel is directed radially outward and is caused to be moved radiallyover said support.

9. In a device for burning solid fuels, a stationary vertically disposedtubular fuel conduit having an open lower end provided with a notchdening a side outlet through which the fuel is adapted to be discharged,a wall of said notch being inwardly curved and extended to define aspiral fuel guide Surface, a rotatable fuel and i'lre bed support forrespectively supporting the fire bed beyond the confines of the conduitand the fuel within said conduit, means for rotating said support, andmeans' on the fuel supporting portion thereof for imparting rotarymotion to the fuel within the conduit.

10. In a device for burning solids fuels, a stationary tubular fuelconduit having an open lower end provided with a notch defining a sideoutlet through which the fuel is adapted tobe discharged, a wall of saidoutlet being curved and extended inwardly beyond the inner surface ofthe conduit to dene a fuel guide, a rotatable fuel and re bed supportfor respectively supporting the fire bed outside of the confines of theconduit and the fuel within the conduit, means for rotating saidsupport, and upstanding means on the fuel supporting portion forimparting rotary movement to the fuel within the conduit so as toadvance the fuel towards the curved and inwardly extended wall of thefuel outlet and effect its discharge therethrough.

11. In a device for burning solid fuels, a driven rotatable fuel andfire bed support having a solid central fuel supporting portion and asurrounding grate portion, means for rotating said support, and astationary fuel conduit of a diameter corresponding approximately to thediameter of the solid central portion of the support and engagedthereby, said` fuel conduit having an open lower end provided with anotch defining a side outlet through which the fuel is adapted to bedischarged, a wall of said outlet forming a convex cam surface merginginto the outer wall of the fuel conduit and towards and against whichthe fuel is moved by the rotation of the support to cause the fuel andre bed to be moved .outwardly over the support.

VIRGINIUS M. CRUIKS'HANK.

